支持热插拔
需要确认如下&mmc1节点中一定不能有non-removable这个属性节点。
/kernel-3.18/arch/arm64/boot/dts/Project_Name.dts

 &mmc1 {
        clk_src = /bits/ 8 ;
        bus-width = ;
        max-frequency = ;
        msdc-sys-suspend;
        cap-sd-highspeed;
        sd-uhs-sdr12;
        sd-uhs-sdr25;
        sd-uhs-sdr50;
        sd-uhs-sdr104;
        sd-uhs-ddr50;
        pinctl = <&mmc1_pins_default>;
        pinctl_sdr104 = <&mmc1_pins_sdr104>;
        pinctl_sdr50 = <&mmc1_pins_sdr50>;
        pinctl_ddr50 = <&mmc1_pins_ddr50>;
        register_setting = <&mmc1_register_setting_default>;
        host_function = /bits/ 8 ;
        cd_level = /bits/ 8 ;
        cd-gpios = <&pio 5 0>;
        /*non-removable;*/
        status = "okay";
};

二、请确认插入和拔出sdcard中断Pin状态

1. 未插入sdcard和插入sdcard的时候相比，中断Pin的电压状态是否有高低变化，如没有变化，请硬件人员检查硬件。
   
   
2. 检查中断Pin在拉高的状态下，电压高度是否满足设计要求，例如拉高状态中断Pin电压应为1.8V，实际测量是否可以达到1.8V
4.     1、未插卡中断Pin是高电平，插入卡中断Pin是低电平
5.         cd_level = /bits/ 8 <MSDC_CD_LOW>;        2、未插卡中断Pin是低电平，插入卡中断Pin是高电平
           cd_level = /bits/ 8 <MSDC_CD_HIGH>